From 752e6676e1c18eb269f4e2b19415c0f1f6c7c7cc Mon Sep 17 00:00:00 2001
From: Vincent Petry <pvince81@owncloud.com>
Date: Tue, 22 Mar 2016 16:54:01 +0100
Subject: [PATCH] Detect user navigating away, don't interpret as ajax error

Whenever a user navigates away, all ajax calls will fail with the same
result like a cross-domain redirect (SSO). To distinguish these cases,
we need to detect whether the error is a result of the user navigating
away. For this, we introduce a new flag that will be set in
"beforeunload".

Additional handling was required for false positives in case "beforeunload" is
used (ex: cancelled upload) and the user cancelled the navigation.
---
 core/js/js.js | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/core/js/js.js b/core/js/js.js
index e90ceaf4e1..584bf1c1c8 100644
--- a/core/js/js.js
+++ b/core/js/js.js
@@ -741,7 +741,9 @@ var OC={
 	 */
 	_processAjaxError: function(xhr) {
 		// purposefully aborted request ?
-		if (xhr.status === 0 && (xhr.statusText === 'abort' || xhr.statusText === 'timeout')) {
+		// this._userIsNavigatingAway needed to distinguish ajax calls cancelled by navigating away
+		// from calls cancelled by failed cross-domain ajax due to SSO redirect
+		if (xhr.status === 0 && (xhr.statusText === 'abort' || xhr.statusText === 'timeout' || this._userIsNavigatingAway)) {
 			return;
 		}
 
@@ -1438,6 +1440,29 @@ function initCore() {
 		$('html').addClass('edge');
 	}
 
+	$(window).on('unload', function() {
+		OC._unloadCalled = true;
+	});
+	$(window).on('beforeunload', function() {
+		// super-trick thanks to http://stackoverflow.com/a/4651049
+		// in case another handler displays a confirmation dialog (ex: navigating away
+		// during an upload), there are two possible outcomes: user clicked "ok" or
+		// "cancel"
+
+		// first timeout handler is called after unload dialog is closed
+		setTimeout(function() {
+			OC._userIsNavigatingAway = true;
+
+			// second timeout event is only called if user cancelled (Chrome),
+			// but in other browsers it might still be triggered, so need to
+			// set a higher delay...
+			setTimeout(function() {
+				if (!OC._unloadCalled) {
+					OC._userIsNavigatingAway = false;
+				}
+			}, 10000);
+		},1);
+	});
 	$(document).on('ajaxError.main', function( event, request, settings ) {
 		if (settings && settings.allowAuthErrors) {
 			return;